Pregnancy favors the occurrence of chorea, a circumstance explicable by the increased irritability of certain nerve centres characteristic of the pregnant woman. The chorea of pregnancy occurs for the most part in primiparæ, it is commoner in young than in older pregnant women, and appears especially in the early months of pregnancy. In the majority of cases the disease undergoes spontaneous cure before the end of the pregnancy, but cases with a fatal termination have been observed. On the other hand, a curative influence in previously subsisting hysteria has been assigned to pregnancy. This in fact only occurs in cases in which the hysterical manifestations have been evoked by influences which are counteracted or removed by the occurrence of pregnancy, such, for instance, as intense longing to bear a child, dissatisfaction with the existing circumstances of married life, etc. Conversely, it is by no means unusual to observe that, in patients who have previously suffered from hysteria, the attacks become more frequent during pregnancy, and that other nervous disturbances associated with the hysteria become more prominent; hysterical paralysis, even, may appear. Very variable also is the influence of pregnancy in epileptics. Most commonly, indeed, a certain quiescence sets in, the attacks becoming less frequent and less severe; but the reverse of this is at times observed. In the domain of the sense organs we observe amblyopia and hemianopia, deafness, and tinnitus aurium, and disorders of taste; all these appear as pure nervous disturbances without known anatomical basis (_Windscheid_). Finally, among neuroses, tetany may be mentioned. In women, this disease occurs almost exclusively during pregnancy and the puerperal state, in the form of paroxysmal spasm, affecting chiefly the extremities, and especially the hands; the spasm is bilateral, tonic in character, and painful. The tetany of pregnancy usually runs a favourable course. The slighter forms of mental disorder consist of perversions of taste and smell. Of actual psychoses occurring during pregnancy, the commonest forms are melancholia and mania. The former condition, which, according to _Ripping_, occurs in 84.4 per cent. of the cases, is usually very severe, and is characterized by a peculiar dreamy condition; it often leads to suicide, or to infanticide immediately after parturition. The psychoses of pregnancy are seen with greater frequency in the second half of pregnancy, they occur especially in primiparæ, and are also commoner in unmarried women. The prognosis is on the whole an unfavorable one; sometimes, indeed, the mental disorder terminates with the pregnancy, but in other cases it continues during the puerperium. Mental alienation occurring in the early months of pregnancy is apt to be less severe and to permit of a more favorable prognosis, than that which makes its appearance during the later months or at the end of the pregnancy.